This invention relates to a magnetic tape cassette and, more specifically, to the improvements in identifiability of the magnetic tape cassette.
Pulse-code modulation recording-reproducing units have been proposed which change acoustic and other analog signals into digital ones, such as PCM signals, and record (or reproduce) the information on a magnetic tape. A recent variety of the PCM recorder-reproducer uses a rotating head to obtain a relatively high recording density. In the PCM recorder-reproducer using a rotating head, a magnetic tape is partly pulled out of a magnetic tape cassette and is wound round a rotating drum where the rotating head is installed for recording or playback.
With the magnetic tape cassette to be used in such a PCM recorder-reproducer it is necessary to seal the magnetic tape as tightly in the cassette as possible; otherwise finger marks and dust deposit on the tape could cause dropouts of signals being reproduced. There must also be provided a large enough space inside the cassette housing for the insertion of guides along which the magnetic tape can be partly taken out for recording or reproduction.
To meet these requirements a magnetic tape cassette has been contrived which includes a slide cover located outside the lower half section of the cassette housing and adapted to slide toward and away from the front face of the cassette and also includes a front lid pivotally secured to the housing so as to turn open or cover the front face. The magnetic tape cassette of the character further incorporates a stopper having pawls engageable with the peripheries of hubs to prevent the roll of tape from loosening due to free rotation of the hubs during the storage or transportation of the cassette. The stopper, except for its pawls, is disposed to be slidable perpendicularly to the axes of rotation of the hubs between, and along, the inner surface of an opaque cover portion outside the see-through window of the upper half housing section and the edges of tape wound on the hubs, so that the pawls projecting from the inner end of the stopper come into or out of engagement with the hub peripheries.
It is customary with the cassette of the type to print information including the length, quality, and grade of the magnetic tape involved on a label and affix the label to a preselected area of the opaque front portion outside the see-through window of the cassette housing. Since the labeled area is very small (approximately 5 cm by 7 cm), the label is liable to contact with the fingers and soiling with finger marks. Another problem is that the lack of proper indication as to the length, quality, kind, and other information on the tape causes confusion among the workers during the manufacture of the cassettes.
It is an object of the present invention to provide a magnetic tape cassette on which pertinent information is easily indicated and, preferably, the grade, kind, and other data are given for easy identification.
Another object of the invention is to increase the portion of the stopper exposed to be visible through the see-through window of the upper half housing section of a magnetic tape cassette.
Still another object of the invention is to improve the production controllability and identifiability of magnetic tape cassettes through clear indication of the grade, use, type, and other pertinent information of the magnetic tape contained.
A further object of the invention is to provide a magnetic tape cassette with improved outward appearance.